#include<stdio.h>


int main() {

	double a, D, d, V, R, r, m;
	scanf("%lf%lf", &D, &d);
	a = 11340;
	R = D / 200, r = d / 200;
	V = 4.0 / 3 * 3.1415926 * (R * R * R - r * r * r);
	m = a * V;
	printf("%lf", m);

	return 0;
}